1. Field of the Invention
The present invention relates to an incinerator for combustion of general refuse and industrial wastes, and an incinerating method employing the same.
2. Description of the Prior Art
Heretofore proposed is a vertical incinerator having a plurality of grates dividing a furnace into a plurality of stages in such a manner that said grates can be freely opened and closed, whereby the refuse charged from the top of the furnace piles up on the grate in the first stage in a sufficient thickness thereon and is then transferred successively to the grate in the succeeding stage or stages while it is burned until it has been finally turned to ashes for discharge from the bottom of the furnace.
However, the refuse generally includes hardly combustible materials such as those rich in moisture and air-impermeable lumps, or including difficultly crushable masses, so that the combustion may not be completed in the upper combustion zone but continue in the lower combustion zone, or wherein plastics melt and drip down, and then ignite in the lower zone of the furnace. For these reasons, the grates supporting the refuse in the upper combustion zone are exposed to intense heat from the reverse surfaces and cannot be sufficiently cooled by blasting cold air against the grates, with the result that the grates tend to be thermally strained or damaged.
Furthermore, the ventilation holes in the grates may be plugged with ashes and foreign matter so as to interfere with the free passage of combustion gases and combustion air, or clinkers may be melted and stuck to the ventilation holes to impede the opening and closing of the grates.